Altering <h1> image replacement logo

Hello lovely forum people. My theme uses CSS Image Replacement to display my logo in the header area. The code that works this magic seems to derive from an <h1> header in ‘header.php’ template, which draws text from my ‘blog name’. This is not ideal for SEO, as I’d like just one <h1> header on each page, drawing text from the ‘title’ of that page.

I’ve read all around the topic today and cannot figure out the correct code to use. So, I’ve improvised a short-term solution, changing <h1> to <h3>, as follows: